IWM vs SPY: Holdings Overlap
iShares · 1941 holdings · $82.2B · as of 2026-03-31
SPYState Street® SPDR® S&P 500® ETF Trust
State Street (SPDR) · 504 holdings · $812.0B · as of 2026-08-06
Holdings snapshots are 128 days apart (IWM: 2026-03-31, SPY: 2026-08-06). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are IWM and SPY?
iShares Russell 2000 ETF (IWM, by iShares) holds 1941 positions; State Street® SPDR® S&P 500® ETF Trust (SPY, by State Street (SPDR)) holds 504. They have 1 holdings in common, and by portfolio weight the two funds are 0.0% identical. In practical terms the pair is essentially distinct, holding almost none of the same securities.
- Overlap by Weight
- 0.0%Sum of the smaller weight of each shared holding
- Shared Holdings
- 1IWM holds 1941 · SPY holds 504
- Weight in Shared Holdings
- IWM 1%·SPY 0%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in IWM
1940 of 1941 positions (99.1% of the fund) are not held by SPY. Showing the top 30 by weight.
Sector Breakdown
| Sector | IWM | SPY |
|---|---|---|
| Information Technology | 13.6% | 37.6% |
| Industrials | 17.9% | 8.8% |
| Health Care | 16.6% | 8.9% |
| Financials | 15.3% | 12.3% |
| Communication Services | 2.5% | 9.7% |
| Other Sectors | 28.2% | 22.6% |
| Unclassified | 5.5% | 0.0% |
Share of each fund's portfolio weight by GICS-style sector, compiled from issuer fund data and our own classification of the holdings, not the issuers' published sector charts. “Unclassified” is weight we could not classify (5% of IWM, 0% of SPY).
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| IWM | +1.8% | +23.0% | +38.6% | +17.1% | +7.5% | +10.8% | 0.88% |
| SPY | +3.4% | +14.0% | +23.7% | +21.2% | +13.3% | +15.3% | 0.97% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in IWM vs SPY →
Shared Holdings(1)
 ECHOEchoStar Corp., Class A | 0.54% | 0.02% | 0.02% |
|---|
Frequently Asked Questions
How much do IWM and SPY overlap?
IWM and SPY overlap by 0.0% of portfolio weight. They share 1 holdings (IWM holds 1941 positions and SPY holds 504), based on each fund's latest SEC-reported holdings.
Is it redundant to own both IWM and SPY?
The two portfolios are 0.0% identical by weight. Owning both is genuine diversification: the funds hold almost none of the same securities.
What are the biggest shared holdings of IWM and SPY?
The largest positions held by both funds are ECHO. Together the top 1 shared positions account for 89% of the total overlap.
What does IWM own that SPY doesn't?
1940 positions (99.1% of IWM) are unique to IWM, led by BE, CDE and FN. In the other direction, 503 positions (99.9% of SPY) are unique to SPY.